Effects of resource chemistry on the composition and function of stream hyporheic biofilms.

Frontiers in Microbiology
By: , and 



Fluvial ecosystems process large quantities of dissolved organic matter as it moves from the headwater streams to the sea. In particular, hyporheic sediments are centers of high biogeochemical reactivity due to their elevated residence time and high microbial biomass and activity. However, the interaction between organic matter and microbial dynamics in the hyporheic zone remains poorly understood. We evaluated how variance in resource chemistry affected the microbial community and its associated activity in experimentally grown hyporheic biofilms. To do this we fed beech leaf leachates that differed in chemical composition to a series of bioreactors filled with sediment from a sub-alpine stream. Differences in resource chemistry resulted in differences in diversity and phylogenetic origin of microbial proteins, enzyme activity, and microbial biomass stoichiometry. Specifically, increased lignin, phenolics, and manganese in a single leachate resulted in increased phenoloxidase and peroxidase activity, elevated microbial biomass carbon:nitrogen ratio, and a greater proportion of proteins of Betaproteobacteria origin. We used this model system to attempt to link microbial form (community composition and metaproteome) with function (enzyme activity) in order to better understand the mechanisms that link resource heterogeneity to ecosystem function in stream ecosystems.
Publication type Article
Publication Subtype Journal Article
Title Effects of resource chemistry on the composition and function of stream hyporheic biofilms.
Series title Frontiers in Microbiology
DOI 10.3389/fmicb.2012.00035
Volume 3
Issue 35
Year Published 2012
Language English
Publisher Elsevier Science
Description 14 p.
Larger Work Type Article
Larger Work Subtype Journal Article
Larger Work Title Frontiers in Microbiology
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